White Petroleum jelly (also called petrolatum) is a mixture of mineral oils and waxes, which form a semisolid jelly-like substance. The purity of petroleum jelly depends on the manufacturing process. Unrefined petroleum jelly may contain harmful ingredients, but refined petroleum jelly is usually safe Petroleum jelly’s benefits come from its main ingredient petroleum, which helps seal your skin with a water-protective barrier. This helps your skin heal and retain moisture. Read on to learn what else you can use petroleum jelly for.